More modern alternative to bittorrent?

Hello. I remember a long time ago I found some protocol that was boasted as a less out-dated version of bittorrent. I think one of its features was that you could update a whatever-their-equivalent-of-a-torrent-is with small changes and those changes could be seeded.

If this sounds familiar, and you know anything about this, I would really appreciate pointing me in the right direction. Thank you.